South Africa's President Jacob Zuma is about to find out who will replace him as leader of the ANC.

The warm, rich, indulgent chuckle of South Africa’s President Jacob Gedleyihlekisa Zuma ripples through a solemn conference chamber in Pretoria.

It’s his trademark - a disarming, seemingly unlimited well of good humour, deployed to break the ice, lighten the mood and wrong-foot his opponents.

Many people who know him talk of Zuma’s extravagant charm.

I remember watching him gleefully bounding on to a stage, one cold night in central Johannesburg in April 2009, to celebrate the election victory that had just elevated him to the post once occupied by President Nelson Mandela. His laughter, his dance moves, his raucous singing - all seemed to promise a new era of confidence and energy for a country finally being led by “one of us” - a charismatic, salt-of-the-earth man rather than his predecessor, the elitist “professor” Thabo Mbeki.